Thrust bearing and rotary machine

Abstract

To suppress erroneous assembly.SOLUTION: The thrust bearing includes a first bearing assembly disposed on a first side in the axial direction with respect to a thrust collar, and a second bearing assembly disposed on a second side in the axial direction with respect to the thrust collar. The first bearing assembly includes a plurality of first pad assemblies each having a first pad surface, and a first carrying case defining a first insertion slot for positioning the plurality of first pad assemblies. The second bearing assembly includes a plurality of second pad assemblies having a second pad surface, and a second carrying case defining a second insertion slot for positioning the plurality of second pad assemblies. The first insertion groove is formed in such a shape that the second pad assembly cannot be inserted to a first prescribed position, and the second insertion groove is formed in such a shape that the first pad assembly cannot be inserted to a second prescribed position.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a thrust bearing and a rotary machine. [Background technology]

[0002] In rotary machines with rotors, such as steam turbines and compressors, bearing devices are used to rotatably support the rotors. Such bearing devices include journal bearings that support the radial load of the rotor and thrust bearings that support the axial load of the rotor.

[0003] For example, Patent Document 1 describes a tilting pad thrust bearing having multiple pads arranged on the outer periphery of the rotating shaft so as to face a thrust collar, and multiple oil filler ports provided between the multiple pads. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-94373 Summary of the Invention [Problem to be solved by the invention]

[0005] In a thrust bearing, pads are arranged axially to sandwich a thrust collar. The axial load generated by the rotor on the thrust bearing is primarily applied to the pads on one side of the thrust collar. In other words, the loads acting on the pads on one side of the thrust collar are significantly different. Therefore, thrust bearing components, such as pads and carrying cases supporting the pads, must be designed with different shapes to optimize the shapes on one side of the thrust collar and the other side of the thrust collar. However, because the thrust bearing components on both sides of the thrust collar are similar, there is a risk of incorrect assembly. For large rotating shafts, disassembly and assembly work can be very complex. Therefore, if incorrect assembly requires repeated disassembly and assembly work, significant losses can result. Therefore, a thrust bearing that can prevent incorrect assembly is needed.

[0006] The present disclosure has been made to solve the above-described problem, and has an object to provide a thrust bearing and a rotary machine that can be prevented from being assembled incorrectly. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, a thrust bearing according to the present disclosure is a thrust bearing that supports an axial load of a rotary shaft that rotates about an axis, via a thrust collar that is arranged to protrude radially outward from the rotary shaft, and includes: a first bearing assembly that is arranged on a first side in the axial direction with respect to the thrust collar; and a second bearing assembly that is opposite in the axial direction to the first bearing assembly with respect to the thrust collar and arranged on a second side in the axial direction with respect to the thrust collar, wherein the first bearing assembly has a first pad surface that faces the thrust collar in the axial direction, and includes a plurality of first pad assemblies that are arranged circumferentially apart from each other with the same shape with respect to the thrust collar; and a plurality of first pad assemblies that are inserted from the radially outside with respect to the first pad surface. the second bearing assembly has a second pad surface facing the thrust collar in the axial direction, and a plurality of second pad assemblies having the same shape and spaced apart in the circumferential direction from the thrust collar; and a second carrying case having a second insertion groove formed therein and capable of holding the second pad assembly inserted from the radially outside at a second predetermined position, the first insertion groove being formed in a shape that prevents the second pad assembly from being inserted up to the first predetermined position, and the second insertion groove being formed in a shape that prevents the first pad assembly from being inserted up to the second predetermined position.

[0008] A rotary machine according to the present disclosure includes the above-described thrust bearing and a rotating shaft rotatably supported by the thrust bearing. [Effects of the Invention]

[0009] According to the thrust bearing and rotary machine of the present disclosure, incorrect assembly can be suppressed. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing a schematic configuration of a steam turbine according to an embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged view of a main portion of the thrust bearing according to the embodiment. [Figure 3] FIG. 2 is a perspective view of a main part showing the inside of a thrust bearing with the upper half of the bearing cover removed according to the embodiment. [Figure 4] 4 is a cross-sectional view taken along line IV-IV in FIG. 2, showing the state of the first bearing assembly in a state facing the first pad surface according to the present embodiment. FIG. [Figure 5] 3 is a cross-sectional view taken along the line VV in FIG. 2, showing the state of the second bearing assembly facing the second pad surface according to the present embodiment. FIG. [Figure 6] 6 is a cross-sectional view of the essential part taken along the line VI-VI in FIG. 2, showing a state in which a first pad assembly is inserted into a first insertion groove of a first carrying case according to the first embodiment. [Figure 7] 7 is a cross-sectional view of a main part corresponding to FIG. 6, illustrating a state in which a second pad assembly is inserted into a first insertion groove of the first carrying case according to the first embodiment. FIG. [Figure 8] 10 is a cross-sectional view of a main part corresponding to FIG. 6, illustrating a state in which a first pad assembly is inserted into a first insertion groove of a first carrying case according to a second embodiment. FIG. [Figure 9] 7 is a cross-sectional view of a main part corresponding to FIG. 6, illustrating a state in which a second pad assembly is inserted into a first insertion groove of a first carrying case according to a second embodiment. FIG. [Figure 10] FIG. 10 is a cross-sectional view of a main part showing a state in which a second pad assembly is inserted into a second insertion groove of a second carrying case according to a second embodiment. [Figure 11] FIG. 10 is a cross-sectional view of a main part showing a state in which a first pad assembly is inserted into a second insertion groove of a second carrying case according to a second embodiment. [Figure 12] FIG. 11 is a cross-sectional view showing a state in which a first key according to a third embodiment is about to be inserted into a second key groove. [Figure 13] FIG. 11 is a cross-sectional view showing a state in which a first key according to a modified example of the third embodiment is about to be inserted into a second key groove. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments for carrying out a thrust bearing and a rotary machine according to the present disclosure will be described with reference to the accompanying drawings. However, the present disclosure is not limited to only these embodiments.

[0012] (Configuration of rotating machines) As shown in FIG. 1 , the rotary machine is a machine in which a rotary shaft 2 is rotatably supported by a thrust bearing 6 relative to a casing 3. Examples of rotary machines include compressors, turbines, motors, and pumps. In this embodiment, as an example of a turbine, a steam turbine 1 will be described as an example of the rotary machine. As shown in FIG. 1 , the steam turbine 1 of this embodiment mainly includes a rotary shaft 2, a casing 3, a plurality of stator blade rows 4, and a bearing unit 5.

[0013] (rotation axis) The rotating shaft (rotor) 2 is rotatable about an axis O within a casing 3. The rotating shaft 2 has a rotating shaft main body 21 and a plurality of rotor blade rows 23.

[0014] For the sake of convenience in the following explanation, the direction in which the axis O extends will be referred to as the axial direction Da. The first side of the axial direction Da will be referred to as the upstream side Dau (one side), and the second side of the axial direction Da will be referred to as the downstream side Dad (the other side). Furthermore, the radial direction Dr of the rotating shaft 2 based on the axis O will be simply referred to as the radial direction Dr. The side of this radial direction Dr that approaches the axis O will be referred to as the inner side Dri of the radial direction Dr, and the side of this radial direction Dr opposite to the inner side Dri of the radial direction Dr will be referred to as the outer side Dro of the radial direction Dr. Furthermore, the circumferential direction Dc of the rotating shaft 2 centered on the axis O will be simply referred to as the circumferential direction Dc.

[0015] The rotating shaft body 21 extends in the axial direction Da around the axis O. The rotating shaft body 21 is supported by the bearing portion 5 relative to the casing 3 so as to be rotatable about the axis O.

[0016] The rotor blade rows 23 are fixed to the outside Dro of the rotor shaft body 21 in the radial direction Dr. A plurality of rotor blade rows 23 are arranged at intervals in the axial direction Da relative to the rotor shaft body 21. In the case of this embodiment, for example, a total of seven rotor blade rows 23 are arranged, from the rotor blade row 23 located most upstream in the axial direction Da at Dau to the rotor blade row 23 located most downstream in the axial direction Da at Dad. Each rotor blade row 23 has a plurality of rotor blades 24 lined up in the circumferential direction Dc.

[0017] (Casing) The casing 3 is formed in a cylindrical shape extending in the axial direction Da with the axis O as its center. The casing 3 rotatably covers the rotating shaft 2. The casing 3 is formed to cover the rotating shaft main body 21 and the plurality of rotor blades 24 from the outside Dro in the radial direction Dr. A main flow path 31 is formed inside the casing 3, through which high-pressure steam S can flow. A plurality of rotor blade rows 23 and stator blade rows 4 are arranged in the main flow path 31.

[0018] In the main flow passage 31, high-pressure steam S flows from the upstream side Dau in the axial direction Da to the downstream side Dad while the pressure gradually decreases. The main flow passage 31 is formed in an annular shape around the rotating shaft main body 21. The main flow passage 31 extends in the axial direction Da across a plurality of rotor blade rows 23 and stator blade rows 4. A portion of the main flow passage 31 is formed by an annular space in which stator blades 41, which will be described later, are arranged.

[0019] The stator vane rows 4 are fixed to the inside Dri of the casing 3 in the radial direction Dr. A plurality of stator vane rows 4 are arranged at intervals in the axial direction Da. In this embodiment, for example, a total of seven stator vane rows 4 are arranged, from the stator vane row 4 located most upstream Dau in the axial direction Da to the stator vane row 4 located most downstream Dad in the axial direction Da. Each stator vane row 4 is arranged next to a corresponding one of the rotor blade rows 23 on the upstream side Dau.

[0020] Each stator vane row 4 has a plurality of stator vanes 41 arranged in the circumferential direction Dc. The stator vanes 41 are arranged at intervals in the circumferential direction Dc. The stator vanes 41 are fixed to the inside Dri of the casing 3 in the radial direction Dr. The stator vanes 41 are fixed to the inner circumferential surface of the casing 3. The inner circumferential surface of the casing 3 is the surface of the casing 3 that faces the inside Dri in the radial direction Dr and faces the main flow path 31. The inner circumferential surface of the casing 3 is the surface that faces the tips of the rotor blades 24 at a position shifted in the axial direction Da from the position where the stator vanes 41 are fixed. One stage is formed by each pair of a stator vane row 4 and one rotor blade row 23 arranged on the downstream side Dad of this stator vane row 4. In other words, one stage is formed by a pair of a stator vane 41 and a rotor blade 24 arranged in the axial direction Da. Therefore, with respect to the plurality of rotor blades 24 arranged in the circumferential direction Dc, the plurality of stator blades 41 arranged in the circumferential direction Dc are arranged on the upstream side Dau in the axial direction Da.

[0021] (bearing part) The bearing portion 5 supports the rotating shaft main body 21 rotatably about the axis O. The bearing portion 5 is disposed inside the casing 3. The bearing portion 5 has a journal bearing 51 and a thrust bearing 6.

[0022] The journal bearings 51 support the rotating shaft body 21 in the axial direction Da at a position close to the end of the rotating shaft body 21 with respect to the multiple stages of the stator vanes 41 and the rotor blades 24. The journal bearings 51 support a load in the radial direction Dr acting on the rotating shaft body 21. A pair of journal bearings 51 are arranged in the axial direction Da so as to sandwich the multiple stages of the stator vanes 41 and the rotor blades 24 therebetween.

[0023] (Thrust bearing) The thrust bearing 6 supports a load in the axial direction Da acting on the rotating shaft body 21. The thrust bearing 6 is arranged in a position closer to the end of the rotating shaft body 21 than the journal bearing 51 on one side. The thrust bearing 6 in this embodiment is arranged in a position closer to the end of the rotating shaft body 21 than the journal bearing 51 located on the upstream side Dau in the axial direction Da of the pair of journal bearings 51. The thrust bearing 6 is a tilting pad bearing.

[0024] As shown in FIG. 2, the thrust bearing 6 supports the rotating shaft 2 via a thrust collar 22. The thrust collar 22 is formed on the rotating shaft 2. The thrust collar 22 is annular and protrudes from the rotating shaft main body 21 to the outer side Dro in the radial direction Dr. The region where the thrust collar 22 is formed is the region supported by the thrust bearing 6. In the case of the steam turbine 1 of this embodiment as shown in FIG. 1, a load in the axial direction Da acting on the rotating shaft main body 21 occurs on the thrust collar 22 so as to move from the upstream side Dau in the axial direction Da toward the downstream side Dad. Therefore, the thrust bearing 6 needs to support a larger load at a position downstream Dad in the axial direction Da relative to the thrust collar 22 than at a position upstream Dau in the axial direction Da.

[0025] As shown in FIGS. 2 and 3, the thrust bearing 6 of this embodiment includes a first bearing assembly 7, a second bearing assembly 8, a bearing cover 9, a first key 11, and a second key 15.

[0026] The first bearing assembly 7 is disposed on the upstream side Dau in the axial direction Da relative to the thrust collar 22. In other words, the first bearing assembly 7 is disposed in a position where the load in the axial direction Da acting on the thrust collar 22 is small. The first bearing assembly 7 is formed in an annular shape centered on the axis O. The first bearing assembly 7 has an inner surface Dri through which the rotating shaft main body 21 can be inserted. The first bearing assembly 7 of this embodiment has a first pad assembly 71 and a first carrying case 75.

[0027] As shown in Fig. 4, a plurality of first pad assemblies 71 (six in this embodiment) are arranged spaced apart in the circumferential direction Dc. All of the first pad assemblies 71 have the same shape. The first pad assemblies 71 are arranged in an annular shape by being spaced apart evenly in the circumferential direction Dc. As shown in Fig. 2, the first pad assembly 71 has a first pad surface 711, a first pad back surface 712, and a first pivot 713.

[0028] The first pad surface 711 faces the thrust collar 22 in the axial direction Da. The first pad surface 711 supports, via lubricant oil, the surface of the thrust collar 22 facing the upstream side Dau in the axial direction Da from the axial direction Da. As shown in FIG. 4, the first pad surface 711 is a fan-shaped flat surface facing the downstream side Dad in the axial direction Da. When viewed from the axial direction Da, the first pad surface 711 is formed in a shape that is symmetrical in the circumferential direction Dc.

[0029] 2, the first pad back surface 712 faces the opposite side in the axial direction Da to the first pad surface 711. The first pad back surface 712 is a fan-shaped flat surface facing the upstream side Dau in the axial direction Da so as to be formed with a smaller outer diameter than the first pad surface 711.

[0030] The first pivot 713 is formed so that the first pad surface 711 can tilt with respect to the thrust collar 22. The first pivot 713 protrudes from the first pad back surface 712 in the axial direction Da. The first pivot 713 protrudes from the first pad back surface 712 to the upstream side Dau in the axial direction Da. The first pivot 713 is in swingable contact with the first carrying case 75.

[0031] 4, the direction in which the rotating shaft 2 rotates in the circumferential direction Dc is the rotation direction R. In the rotation direction R, the direction to which the rotating shaft 2 will rotate from now on and one side of the circumferential direction Dc is the forward side Rf of the rotation direction R. In addition, in the rotation direction R, the opposite side of the circumferential direction Dc from the forward side Rf and the other side of the circumferential direction Dc is the rear side Rb of the rotation direction R.

[0032] When the first pad assembly 71 is viewed from the axial direction Da so as to face the first pad surface 711, the first pivot 713 is positioned at a position shifted forward Rf in the rotational direction R relative to the center position in the circumferential direction Dc of the first pad back surface 712 (first pad surface 711).

[0033] The first carrying case 75 is capable of defining the positions of the multiple first pad assemblies 71. The first carrying case 75 is formed in an annular shape centered on the axis O. The first carrying case 75 is structured to be separable into upper and lower halves in the vertical direction. Therefore, by placing the lower half of the first carrying case 75 below the rotating shaft body 21 and the upper half above the rotating shaft body 21, the rotating shaft body 21 is inserted into the inner surface Dri. In other words, the first carrying case 75 can be attached to the rotating shaft body 21 before the first pad assemblies 71 are attached. As shown in FIG. 2, the first carrying case 75 is formed with multiple first insertion grooves 751.

[0034] The first insertion groove 751 allows the first pad assembly 71 to be inserted from the outer side Dro in the radial direction Dr. The first insertion groove 751 is recessed from the outer peripheral surface of the first carrying case 75 toward the inner side Dri in the radial direction Dr. The first insertion groove 751 is capable of holding the first pad assembly 71 inserted from the outer side Dro in the radial direction Dr at a first predetermined position. Here, the first predetermined position is an appropriate position for the first carrying case 75 where the first pad assembly 71 can stably receive a load when used in a thrust bearing 6. In this embodiment, at the first predetermined position, the first pad assembly 71 does not protrude from the outer peripheral surface of the first carrying case 75 toward the outer side Dro in the radial direction Dr. Only one first pad assembly 71 can be inserted into each first insertion groove 751. Therefore, a plurality of first insertion grooves 751 are formed for each first carrying case 75. The plurality of first insertion grooves 751 are arranged at equal intervals in the circumferential direction Dc. The multiple first insertion grooves 751 are all formed in the same shape. When viewed from the axial direction Da, the first insertion grooves 751 are formed in an asymmetric shape in the circumferential direction Dc. The first insertion grooves 751 are formed in a shape that prevents the second pad assembly 81, which will be described later, from being inserted up to a first predetermined position.

[0035] As shown in FIG. 3 , the first carrying case 75 of this embodiment includes a first refueling nozzle 752 and a first case main body 753. The first refueling nozzle 752 is capable of spraying lubricating oil toward the thrust collar 22. As shown in FIG. 4 , the first refueling nozzle 752 has a plurality of openings for spraying lubricating oil at the center in the circumferential direction Dc. The first refueling nozzle 752 sprays lubricating oil toward the downstream side Dad in the axial direction Da. The first refueling nozzle 752 is disposed between adjacent first pad assemblies 71. The first refueling nozzle 752 is disposed at a position not overlapping with the first insertion groove 751 when viewed from the axial direction Da. The first refueling nozzle 752 is formed such that its width in the circumferential direction Dc narrows from the upstream side Dau in the axial direction Da toward the downstream side Dad (from the first pad back surface 712 toward the first pad surface 711 in the axial direction Da).

[0036] 6, a plurality of first fuel filler nozzles 752 are fixed to the first case body 753. A first insertion groove 751 is formed in the first case body 753. In the first case body 753, the first insertion groove 751 is formed between two first fuel filler nozzles 752 adjacent to each other in the circumferential direction Dc.

[0037] In the present embodiment, the first insertion groove 751 has an outer side Dro region in the radial direction Dr defined by the first case main body 753. Therefore, the width of the first insertion groove 751 in the circumferential direction Dc of the outer side Dro region in the radial direction Dr is determined by the first case main body 753. Furthermore, the first insertion groove 751 has an inner side Dri region in the radial direction Dr defined by the two first fuel fill nozzles 752 adjacent to each other in the circumferential direction Dc. Therefore, the width of the first insertion groove 751 in the circumferential direction Dc of the inner side Dri region in the radial direction Dr is determined by the two first fuel fill nozzles 752 adjacent to each other in the circumferential direction Dc. Furthermore, when the first pad assembly 71 is inserted into the first insertion groove 751, the first case main body 753 and the first fuel fill nozzle 752 do not interfere with (contact with) the first pad assembly 71. On the other hand, when the second pad assembly 81 is inserted into the first insertion groove 751, only the first case body 753 interferes with (contacts) the second pad assembly 81, and the second pad assembly 81 cannot be inserted up to the first specified position.

[0038] As shown in Figures 2 and 3, the second bearing assembly 8 is disposed inversely in the axial direction Da relative to the first bearing assembly 7, with the thrust collar 22 as the reference. In other words, the second bearing assembly 8 is disposed downstream in the axial direction Da relative to the thrust collar 22. Therefore, the second bearing assembly 8 is disposed in a position where a large axial load Da occurs on the thrust collar 22. Therefore, the second bearing assembly 8 is capable of supporting a larger load than the first bearing assembly 7. The second bearing assembly 8 is formed in an annular shape centered on the axis O. The rotating shaft main body 21 can be inserted into the inner surface Dri of the second bearing assembly 8. The first bearing assembly 7 and the second bearing assembly 8 have the same size of the axial direction Da. The second bearing assembly 8 of this embodiment includes a second pad assembly 81 and a second carrying case 85.

[0039] As shown in FIG. 5, a plurality of second pad assemblies 81 (six in this embodiment) are arranged spaced apart in the circumferential direction Dc. The same number of second pad assemblies 81 as the number of first pad assemblies 71 are arranged. All of the multiple second pad assemblies 81 have the same shape. In this embodiment, the second pad assemblies 81 are formed with a shape different from that of the first pad assembly 71. Although the second pad assembly 81 has a shape similar to that of the first pad assembly 71, the shapes are not completely identical, and the second pad assembly 81 has a different outer diameter from that of the first pad assembly 71. Furthermore, the second pad assembly 81 differs from the first pad assembly 71 in that the position of a second pivot 813 (described later) is shifted in the circumferential direction Dc from the position of the first pivot 713. The multiple second pad assemblies 81 are arranged in an annular shape by being spaced apart evenly in the circumferential direction Dc. As shown in FIG. 2, the second pad assembly 81 has a second pad surface 811, a second pad back surface 812, and a second pivot 813.

[0040] The second pad surface 811 faces the thrust collar 22 in the axial direction Da. The second pad surface 811 is a sector-shaped flat surface facing the upstream side Dau in the axial direction Da. The second pad surface 811 supports the surface of the thrust collar 22 facing the downstream side Dad in the axial direction Da from the axial direction Da via lubricating oil. The second pad surface 811 is disposed in a direction facing the first pad surface 711 in the axial direction Da. As shown in FIG. 5, the second pad surface 811 is formed in a shape symmetrical in the circumferential direction Dc when viewed from the axial direction Da. The second pad surface 811 has a shape that is mirror-symmetrical (plane symmetry with respect to a virtual plane passing through the axis O) with the first pad surface 711 across the thrust bearing 6, as if they were viewed in a mirror image.

[0041] 2, the second pad back surface 812 faces the opposite side in the axial direction Da to the second pad surface 811. The second pad back surface 812 is a fan-shaped flat surface facing the downstream side Dad in the axial direction Da so as to have a smaller outer diameter than the second pad surface 811. The second pad back surface 812 has a different outer diameter from the first pad back surface 712.

[0042] The second pivot 813 is formed so that the second pad surface 811 can tilt with respect to the thrust collar 22. The second pivot 813 protrudes from the second pad back surface 812 in the axial direction Da. The second pivot 813 protrudes from the second pad back surface 812 to the downstream side Dad in the axial direction Da. The second pivot 813 is in contact with the second carrying case 85 in a swingable state.

[0043] As shown in FIG. 5 , when the second pad assembly 81 is viewed from the axial direction Da so as to face the second pad surface 811, the second pivot 813 is disposed at a position shifted forward Rf in the rotational direction R with respect to the center of the second pad back surface 812 (second pad surface 811) in the circumferential direction Dc. Therefore, when the first pad assembly 71 and the second pad assembly 81 are viewed from the axial direction Da with the first pad surface 711 and the second pad surface 811 facing each other in the axial direction Da and overlapping in the circumferential direction Dc and the radial direction Dr, the first pivot 713 and the second pivot 813 are disposed to overlap in the circumferential direction Dc. Therefore, the first pivot 713 and the second pivot 813 are disposed at positions that are mirror-symmetrical. In other words, the position of the first pivot 713 on the first pad back surface 712 of the first pad assembly 71 and the position of the second pivot 813 on the second pad back surface 812 of the second pad assembly 81 are shifted in the circumferential direction Dc.

[0044] The second carrying case 85 is capable of defining the positions of the multiple second pad assemblies 81. The second carrying case 85 is formed in an annular shape centered on the axis O. The second carrying case 85 is structured so that it can be separated into upper and lower halves in the vertical direction. Therefore, by placing the lower half of the second carrying case 85 below the rotating shaft body 21 and the upper half above the rotating shaft body 21, the rotating shaft body 21 is inserted into the inner surface Dri. In other words, the first carrying case 75 can be attached to the rotating shaft body 21 before the first pad assemblies 71 are attached. As shown in FIG. 2, the second carrying case 85 is formed with multiple second insertion grooves 851.

[0045] The second insertion groove 851 allows the second pad assembly 81 to be inserted from the outer side Dro in the radial direction Dr. The second insertion groove 851 is recessed from the outer peripheral surface of the second carrying case 85 toward the inner side Dri in the radial direction Dr. The second insertion groove 851 is capable of holding the second pad assembly 81 inserted from the outer side Dro in the radial direction Dr at a second predetermined position. Here, the second predetermined position is an appropriate position for the second carrying case 85 where the second pad assembly 81 can stably receive a load when used in the thrust bearing 6. Only one second pad assembly 81 can be inserted into each second insertion groove 851. Therefore, a plurality of second insertion grooves 851 are formed per second carrying case 85. The multiple second insertion grooves 851 are arranged at equal intervals in the circumferential direction Dc. All of the multiple second insertion grooves 851 are formed with the same shape. The second insertion grooves 851 are formed with an asymmetric shape in the circumferential direction Dc when viewed from the axial direction Da. The second insertion groove 851 has a shape different from that of the first insertion groove 751. The second insertion groove 851 is formed in a shape that prevents the first pad assembly 71 from being inserted up to the second specified position.

[0046] As shown in FIG. 3, the second carrying case 85 of this embodiment includes a second refueling nozzle 852 and a second case main body 853. The second refueling nozzle 852 is capable of spraying lubricating oil toward the thrust collar 22. As shown in FIG. 5, the second refueling nozzle 852 has a plurality of openings for spraying lubricating oil at the center in the circumferential direction Dc. The second refueling nozzle 852 is disposed between adjacent second pad assemblies 81. The second refueling nozzle 852 is disposed at a position that does not overlap with the second insertion groove 851 when viewed from the axial direction Da. The second refueling nozzle 852 is formed so that its width in the circumferential direction Dc narrows from the downstream side Dad to the upstream side Dau in the axial direction Da (approaching from the second pad back surface 812 to the second pad surface 811 in the axial direction Da). The second refueling nozzle 852 is formed in the same shape as the first refueling nozzle 752.

[0047] 3, a plurality of second fuel fill nozzles 852 are fixed to the second case body 853. A second insertion groove 851 is formed in the second case body 853. In the second case body 853, the second insertion groove 851 is disposed between two second fuel fill nozzles 852 adjacent to each other in the circumferential direction Dc.

[0048] In the present embodiment, the second insertion groove 851 has an outer side Dro region in the radial direction Dr defined by the second case main body 853. Therefore, the width of the second insertion groove 851 in the circumferential direction Dc of the outer side Dro region in the radial direction Dr is determined by the second case main body 853. Furthermore, the second insertion groove 851 has an inner side Dri region in the radial direction Dr defined by the two second fuel supply nozzles 852 adjacent to each other in the circumferential direction Dc. Therefore, the width of the second insertion groove 851 in the circumferential direction Dc of the inner side Dri region in the radial direction Dr is determined by the two second fuel supply nozzles 852 adjacent to each other in the circumferential direction Dc. Furthermore, when the second pad assembly 81 is inserted into the second insertion groove 851, the second case main body 853 and the second fuel supply nozzle 852 do not interfere with (contact) the second pad assembly 81. On the other hand, when the first pad assembly 71 described later is inserted into the second insertion groove 851, only the second case body 853 interferes with (contacts) the first pad assembly 71, making it impossible for the first pad assembly 71 to be inserted up to the second specified position.

[0049] As described above, the shapes of the first pad assembly 71 and the second pad assembly 81 are different from the shapes of the first insertion groove 751 and the second insertion groove 851. Specifically, as shown in FIGS. 4 and 6 , when the first pad assembly 71 is inserted into the first insertion groove 751, the first pad assembly 71 does not protrude from the outer peripheral surface of the first carrying case 75 to the outside Dro in the radial direction Dr. In other words, when the first pad assembly 71 is inserted into the first insertion groove 751, the first pad assembly 71 is inserted into the first carrying case 75 up to a first predetermined position. Therefore, the first insertion groove 751 is formed in a shape that allows the first pad assembly 71 to be inserted up to the first predetermined position without interfering with the first carrying case 75.

[0050] 7, the first insertion groove 751 is formed in a shape that causes the second pad assembly 81 to protrude from the outer peripheral surface of the first carrying case 75 toward the outside Dro in the radial direction Dr when the second pad assembly 81 is inserted. In other words, when the second pad assembly 81 is inserted, the first insertion groove 751 prevents the second pad assembly 81 from being inserted into the first carrying case 75 up to a first predetermined position. The first insertion groove 751 is formed in a shape that prevents the second pad assembly 81 from interfering with the first carrying case 75 and from being inserted up to the first predetermined position. More specifically, the first insertion groove 751 is formed so that the second pad assembly 81 and the first case main body 753 come into contact with each other when the second pad assembly 81 is inserted.

[0051] 5, the second insertion groove 851 is formed in a shape that prevents the second pad assembly 81 from protruding from the outer peripheral surface of the second carrying case 85 toward the outside Dro in the radial direction Dr when the second pad assembly 81 is inserted. In other words, when the second pad assembly 81 is inserted into the second insertion groove 851, the second pad assembly 81 is inserted into the second carrying case 85 up to a second predetermined position. Therefore, the second insertion groove 851 is formed in a shape that allows the second pad assembly 81 to be inserted up to the second predetermined position without interfering with the second carrying case 85.

[0052] On the other hand, the second insertion groove 851 is formed in a shape that causes the first pad assembly 71 to protrude from the outer circumferential surface of the second carrying case 85 toward the outside Dro in the radial direction Dr when the first pad assembly 71 is inserted. In other words, when the first pad assembly 71 is inserted, the second insertion groove 851 prevents the first pad assembly 71 from being inserted into the second carrying case 85 up to a second predetermined position. The second insertion groove 851 is formed in a shape that prevents the first pad assembly 71 from interfering with the second carrying case 85 and from being inserted up to the second predetermined position. More specifically, the second insertion groove 851 is formed so that the first pad assembly 71 and the second case main body 853 come into contact with each other when the first pad assembly 71 is inserted.

[0053] As shown in FIG. 2 , the bearing cover 9 is capable of accommodating the first bearing assembly 7 and the second bearing assembly 8 therein. The bearing cover 9 covers the first bearing assembly 7 and the second bearing assembly 8 together with the thrust collar 22. The bearing cover 9 is formed in a cylindrical shape extending in the axial direction Da with the axis O as its center. The rotating shaft body 21 is inserted through the center of the bearing cover 9. The bearing cover 9 in this embodiment is formed as a separate member from the casing 3. Note that the bearing cover 9 is not limited to being a separate member from the casing 3, and may be formed integrally with the casing 3. The bearing cover 9 has a structure that can be separated into upper and lower parts in the vertical direction. Therefore, when the lower half of the bearing cover 9 is positioned below the rotating shaft body 21, the thrust collar 22, first bearing assembly 7, and second bearing assembly 8 are positioned inside, and the upper half is closed from above the rotating shaft body 21, the rotating shaft body 21 is inserted into the inner side Dri.

[0054] 2 and 4, the first key 11 determines the position of the first bearing assembly 7 in the circumferential direction Dc relative to the bearing cover 9. Only one first key 11 is provided for the bearing cover 9 and the first bearing assembly 7. The first key 11 is provided in the upper half of the bearing cover 9 and the first bearing assembly 7. The first key 11 is received in a first key groove 110 formed in the first carrying case 75 and the bearing cover 9.

[0055] Specifically, the first key groove 110 has an inner first key groove 111 formed in the first carrying case 75 and an outer first key groove 112 formed in the bearing cover 9. The inner first key groove 111 is recessed from the outer peripheral surface of the first carrying case 75 (the surface facing the outer side Dro in the radial direction Dr) toward the inner side Dri in the radial direction Dr. The inner first key groove 111 is recessed from the outer peripheral surface of the first case main body 753 toward the inner side Dri in the radial direction Dr. The inner first key groove 111 allows a portion of the first key 11 to be inserted in a state where the portion cannot move in the axial direction Da and the circumferential direction Dc. The inner first key groove 111 is formed with a depth that allows a portion of the inserted first key 11 to protrude toward the outer side Dro in the radial direction Dr.

[0056] The outer first key groove 112 is recessed from the inner circumferential surface of the bearing cover 9 (the surface facing the inner side Dri in the radial direction Dr) to the outer side Dro in the radial direction Dr. The outer first key groove 112 is recessed from the inner circumferential surface of the upper half bearing cover 9 to the inner side Dri in the radial direction Dr. The outer first key groove 112 allows a portion of the first key 11 to be inserted in a state where it cannot move in the axial direction Da or the circumferential direction Dc. The outer first key groove 112 is formed with a depth that allows the first key 11 to be housed therein when it is inserted into the inner first key groove 111 and with a portion of it protruding.

[0057] As shown in Figures 2 and 5, the second key 15 determines the position of the second bearing assembly 8 in the circumferential direction Dc relative to the bearing cover 9. Only one second key 15 is provided for the bearing cover 9 and the second bearing assembly 8. The second key 15 is a separate member disposed apart from the first key 11. The second key 15 is disposed in the upper half of the bearing cover 9 and the second bearing assembly 8. The second key 15 is received in a second key groove 150 formed in the second carrying case 85 and the bearing cover 9. The second key 15 in this embodiment is formed in the same shape as the first key 11. Therefore, the second key groove 150 is also formed in the same shape as the first key groove 110.

[0058] Specifically, the second key groove 150 has an inner second key groove 151 formed in the second carrying case 85 and an outer second key groove 152 formed in the bearing cover 9. The inner second key groove 151 is recessed from the outer peripheral surface of the second carrying case 85 (the surface facing the outer side Dro in the radial direction Dr) toward the inner side Dri in the radial direction Dr. The inner second key groove 151 is recessed from the outer peripheral surface of the second case main body 853 toward the inner side Dri in the radial direction Dr. The inner second key groove 151 allows a portion of the second key 15 to be inserted in a state where the portion cannot move in the axial direction Da and the circumferential direction Dc. The inner second key groove 151 is formed with a depth that allows a portion of the inserted second key 15 to protrude toward the outer side Dro in the radial direction Dr.

[0059] The outer second key groove 152 is recessed from the inner circumferential surface of the bearing cover 9 (the surface facing the inner side Dri in the radial direction Dr) toward the outer side Dro in the radial direction Dr. The outer second key groove 152 is recessed from the inner circumferential surface of the upper half bearing cover 9 toward the inner side Dri in the radial direction Dr. The outer second key groove 152 is formed away from the outer first key groove 112. The outer second key groove 152 allows a portion of the second key 15 to be inserted into it in a state where it cannot move in the axial direction Da or the circumferential direction Dc. The outer second key groove 152 is formed with a depth that allows the first key 11 to be housed therein when it is inserted into the inner second key groove 151 and with a portion of it protruding.

[0060] (Action and effect) In the thrust bearing 6 configured as described above, the first pad assembly 71 is inserted into the first insertion hole from the outer side Dro in the radial direction Dr, thereby assembling the first pad assembly 71 to the first carrying case 75, thereby configuring the first bearing assembly 7. Similarly, the second pad assembly 81 is inserted into the second insertion hole from the outer side Dro in the radial direction Dr, thereby assembling the second pad assembly 81 to the second carrying case 85, thereby configuring the second bearing assembly 8. This ensures ease of installation when installing the first pad assembly 71 and the second pad assembly 81. Furthermore, the first insertion groove 751 can hold the first pad assembly 71 at a first predetermined position, but prevents the second pad assembly 81 from being inserted up to the first predetermined position. The second insertion groove 851 can hold the second pad assembly 81 at a second predetermined position, but prevents the first pad assembly 71 from being inserted up to the second predetermined position. Therefore, the second pad assembly 81 cannot be attached to the first carrying case 75, while the attachability of the first pad assembly 71 to the first carrying case 75 is ensured. Similarly, the first pad assembly 71 cannot be attached to the second carrying case 85, while the attachability of the second pad assembly 81 to the second carrying case 85 is ensured. As a result, it is possible to prevent the second pad assembly 81 from being erroneously attached to the first carrying case 75, or the first pad assembly 71 from being erroneously attached to the second carrying case 85. In this way, it is possible to prevent parts of different combinations from being attached to the thrust bearing 6, thereby preventing incorrect assembly.

[0061] Furthermore, the first insertion groove 751 is formed so that when the first pad assembly 71 is inserted, the first insertion groove 751 does not protrude from the outer peripheral surface of the first carrying case 75 to the outer side Dro in the radial direction Dr. On the other hand, when the second pad assembly 81 is inserted, the first insertion groove 751 is formed so that the second pad assembly 81 protrudes from the outer peripheral surface of the first carrying case 75 to the outer side Dro in the radial direction Dr. Similarly, the second insertion groove 851 is formed so that when the second pad assembly 81 is inserted, the second insertion groove 851 does not protrude from the outer peripheral surface of the second carrying case 85 to the outer side Dro in the radial direction Dr. On the other hand, when the first pad assembly 71 is inserted, the second insertion groove 851 is formed so that the first pad assembly 71 protrudes from the outer peripheral surface of the second carrying case 85 to the outer side Dro in the radial direction Dr. In other words, a member protrudes from the outer peripheral surface of the first carrying case 75 or the second carrying case 85 only when the incorrect first pad assembly 71 or second pad assembly 81 is attached. Therefore, if the second pad assembly 81 is mistakenly attached to the first carrying case 75, or if the first pad assembly 71 is mistakenly attached to the second carrying case 85, the assembly cannot be completed. This makes it possible to immediately detect any assembly errors.

[0062] Furthermore, the first insertion groove 751 is formed between two first fuel filler nozzles 752, and when the second pad assembly 81 is inserted, the second pad assembly 81 comes into contact with the first case main body 753. Similarly, the second insertion groove 851 is formed between two second fuel filler nozzles 852, and when the first pad assembly 71 is inserted, the first pad assembly 71 comes into contact with the second case main body 853. Therefore, simply by changing the shapes of the first case main body 753 and the second case main body 853, it is possible to prevent the second pad assembly 81 from being erroneously attached to the first carrying case 75 or the first pad assembly 71 from being erroneously attached to the second carrying case 85. Furthermore, the shapes of the first insertion groove 751 and the second insertion groove 851 can be changed without being affected by the shapes of the first fuel filler nozzle 752 and the second fuel filler nozzle 852. Therefore, as in this embodiment, the first fuel filler nozzle 752 and the second fuel filler nozzle 852 can have the same shape.

[0063] Furthermore, in a rotary machine such as the steam turbine 1 that is equipped with such a thrust bearing 6, it is possible to prevent parts from being assembled incorrectly in the first bearing assembly 7 and the second bearing assembly 8. This makes it possible to prevent work errors when assembling the steam turbine 1 and improve workability.

[0064] Second Embodiment Next, a thrust bearing 6A according to a second embodiment of the present disclosure will be described. In the second embodiment described below, components common to the first embodiment will be denoted by the same reference numerals in the drawings, and descriptions thereof will be omitted. The thrust bearing 6A of the second embodiment differs from the first embodiment in the shapes of the first insertion groove 751A and the second insertion groove 851.

[0065] 8, in the first carrying case 75A of the second embodiment, the first fuel filler nozzle 752A has a plurality of openings for spraying lubricating oil at positions shifted from the center in the circumferential direction Dc. The first fuel filler nozzle 752A is formed to have a larger width in the circumferential direction Dc than the first fuel filler nozzle 752 of the first embodiment. As a result, the first insertion groove 751A has a different shape from the first insertion groove 751 of the first embodiment.

[0066] When the first pad assembly 71 is inserted into the first insertion groove 751A, similar to the first embodiment, the first case body 753A and the first fuel filler nozzle 752A do not interfere with (contact) the first pad assembly 71. On the other hand, when the second pad assembly 81 is inserted into the first insertion groove 751A, as shown in Fig. 9, unlike the first embodiment, the first case body 753A does not interfere with (contact) the first pad assembly 71. Instead, when the second pad assembly 81 is inserted into the first insertion groove 751A, only the first fuel filler nozzle 752A interferes with (contacts) the second pad assembly 81, and the second pad assembly 81 cannot be inserted up to the first specified position.

[0067] 10, a second carrying case 85A of the second embodiment is similar to the first carrying case 75A. Specifically, in the second carrying case 85A, a second fuel filler nozzle 852A has multiple openings for spraying lubricating oil at positions offset from the center in the circumferential direction Dc. The second fuel filler nozzle 852A is formed with a larger width in the circumferential direction Dc than the second fuel filler nozzle 852 of the first embodiment. As a result, the second insertion groove 851A has a different shape from the second insertion groove 851 of the first embodiment.

[0068] When the second pad assembly 81 is inserted into the second insertion groove 851A, similar to the first embodiment, the second case body 853A and the second fuel filler nozzle 852A do not interfere with (contact) the second pad assembly 81. On the other hand, when the first pad assembly 71 is inserted into the second insertion groove 851A, as shown in Fig. 11 , unlike the first embodiment, the second case body 853A does not interfere with (contact) the first pad assembly 71. Instead, when the first pad assembly 71 is inserted into the second insertion groove 851A, only the second fuel filler nozzle 852A interferes with (contacts) the first pad assembly 71, and the first pad assembly 71 cannot be inserted up to the second specified position.

[0069] (Action and effect) In the thrust bearing 6 of the second embodiment, the first insertion groove 751A is formed between two first fuel filler nozzles 752A, and when the second pad assembly 81 is inserted, the second pad assembly 81 and the first fuel filler nozzle 752A come into contact with each other. Similarly, the second insertion groove 851 is formed between two second fuel filler nozzles 852A, and when the first pad assembly 71 is inserted, the first pad assembly 71 and the second fuel filler nozzle 852A come into contact with each other. Therefore, simply by changing the shapes of the first fuel filler nozzle 752A and the second fuel filler nozzle 852A, it is possible to prevent the second pad assembly 81 from being erroneously attached to the first carrying case 75A or the first pad assembly 71 from being erroneously attached to the second carrying case 85A. Furthermore, because the shapes of the first fuel filler nozzle 752A and the second fuel filler nozzle 852A are different, which are easy to recognize from the outside, the first carrying case 75A and the second carrying case 85A can be easily recognized.

[0070] Third Embodiment Next, a thrust bearing 6B according to a third embodiment of the present disclosure will be described. In the second embodiment described below, components common to the first embodiment will be denoted by the same reference numerals in the drawings, and descriptions thereof will be omitted. The thrust bearing 6B of the second embodiment differs from the first embodiment in the shapes of the first key 11B and the second key 15.

[0071] In the third embodiment, the first key 11B and the second key 15 are formed in any one of the following shapes. First, the first key 11B is formed in a shape that cannot be accommodated in the second key groove 150, and the second key 15 is formed in a shape that cannot be accommodated in the first key groove 110. Second, the first key 11B is formed in a shape that cannot be accommodated in the second key groove 150, and the second key 15 is formed in a shape that can be accommodated in the first key groove 110. Third, the first key 11B is formed in a shape that can be accommodated in the second key groove 150, and the second key 15 is formed in a shape that can be accommodated in the first key groove 110.

[0072] The shape that cannot be accommodated in the first key groove 110 and the second key groove 150 refers to, for example, a shape that prevents at least one of the first key 11B and the second key 15 from being accommodated completely in the first key groove 110 and the second key groove 150. As an example, a shape that prevents the first key 11B from being inserted into the second key groove 150, as shown in FIG. 12 , will be described. The first key 11B is formed in a shape that prevents it from being inserted into either the inner second key groove 151 or the outer second key groove 152. Specifically, the first key 11B is formed to be thicker (larger) in the circumferential direction Dc than the second key 15. Furthermore, because the first key 11B is longer in the circumferential direction Dc than the second key 15, the second key groove 150 is formed to be longer in the circumferential direction Dc than the second key groove 150 so that the first key groove 110 can be accommodated therein. Therefore, the first key 11B cannot be inserted into either the inner second key groove 151 or the outer second key groove 152.

[0073] (Action and effect) In the thrust bearing 6 configured in the third embodiment, at least one of the first key 11B and the second key 15 cannot be accommodated in either the first key groove 110 or the second key groove 150. This makes it impossible to assemble the first bearing assembly 7 and the second bearing assembly 8 to the bearing cover 9. Therefore, if the mounting positions of the first bearing assembly 7 and the second bearing assembly 8 relative to the thrust collar 22 are reversed, assembly cannot be completed. This makes it possible to immediately detect an error in the mounting positions of the first bearing assembly 7 and the second bearing assembly 8.

[0074] Furthermore, as in this embodiment, by making the first key 11B larger than the second key 15 and by giving the first key 11B a shape that prevents it from being inserted into the inner second key groove 151, the first key 11B cannot be inserted into the inner second key groove 151. Therefore, any errors in the installation positions of the first bearing assembly 7 and the second bearing assembly 8 can be immediately detected before the bearing cover 9 is closed.

[0075] In particular, when the first key 11B is formed large in the circumferential direction Dc, errors in the installation positions of the first bearing assembly 7 and the second bearing assembly 8 can be immediately detected by simple processing that simply changes the shape of the first key 11B, which is a small part among the parts of the thrust bearing 6.

[0076] Furthermore, in this embodiment, the first bearing assembly 7 and the second bearing assembly 8 have the same size in the axial direction Da. In this way, even if the external shapes of the first bearing assembly 7 and the second bearing assembly 8 are similar, simply by changing the shape of the first key 11B, it is possible to immediately detect any errors in the mounting positions of the first bearing assembly 7 and the second bearing assembly 8.

[0077] <Modification of the third embodiment> As a modified example of the third embodiment, at least one of the first key 11C and the second key 15 may be shaped so as to be unable to be inserted into the first key groove 110 and the second key groove 150. For example, as shown in FIG. 13 , the first key 11C may be shaped so as to be unable to be partially inserted into the second key groove 150. As an example, a shape in which the first key 11C is shaped so as to be unable to be partially inserted into the second key groove 150 will be described. The first key 11C is shaped so as to be insertable into the inner second key groove 151 but unable to be inserted into the outer second key groove 152. Specifically, the first key 11C is longer (larger) in the radial direction Dr than the second key 15. Furthermore, although the first key 11C is longer in the radial direction Dr than the first key groove 110 and the second key groove 150, the axial dimensions Da and the circumferential dimensions Dc are the same. Furthermore, the axial dimensions Da and the circumferential dimensions Dc of the inner first key groove 111 and the inner second key groove 151 are the same. Therefore, the first key 11C can be inserted only into the inner second key groove 151, but cannot be inserted into the outer second key groove 152.

[0078] (Action and effect) Even in the thrust bearing 6C of the modified example of the third embodiment, the first key 11C cannot be accommodated in the second key groove 150. Therefore, the first bearing assembly 7 and the second bearing assembly 8 cannot be assembled to the bearing cover 9. Therefore, if the mounting positions of the first bearing assembly 7 and the second bearing assembly 8 relative to the thrust collar 22 are reversed, the assembly cannot be completed. This makes it possible to immediately detect an error in the mounting positions of the first bearing assembly 7 and the second bearing assembly 8.

[0079] (Other embodiments) The above describes in detail the embodiments of the present disclosure with reference to the drawings, but the specific configuration is not limited to this embodiment, and design changes and the like are also included within the scope that does not deviate from the gist of the present disclosure.

[0080] The rotary machine equipped with the thrust bearing 6 is not limited to the steam turbine 1 as in this embodiment. The rotary machine may be a compressor, a pump, or a motor as long as it has a rotating shaft 2 supported by the thrust bearing 6.

[0081] Furthermore, in the thrust bearing 6, the first bearing assembly 7 is not limited to a structure in which it is disposed upstream Dau in the axial direction Da relative to the thrust collar 22 and the second bearing assembly 8. In the thrust bearing 6, the first bearing assembly 7 may be arranged such that the second bearing assembly 8 is disposed in a position that receives a large load and the first bearing assembly 7 is disposed in a position that receives a small load, depending on the rotating shaft 2 that it supports.

[0082] Furthermore, the number of first pad assemblies 71 and second pad assemblies 81 is not limited to six as in this embodiment. It is sufficient that a plurality of first pad assemblies 71 and second pad assemblies 81 are arranged, and the number may be five or less, or seven or more.

[0083] Furthermore, the second key 15 in the first embodiment may be formed in the same shape as or a different shape from the first key 11. Therefore, the second key groove 150 may also be formed in the same shape as or a different shape from the first key groove 110.

[0084] Furthermore, in the third embodiment, the first keys 11B and 11C are not limited to being larger than the second keys 15. The second keys 15 may be formed larger than the first keys 11B and 11C.

[0085] <Additional Notes> The thrust bearing 6 and the steam turbine 1 according to the embodiment can be understood, for example, as follows.

[0086] (1) A thrust bearing 6 according to a first aspect is a thrust bearing 6 that supports a load in an axial direction Da of a rotating shaft 2 that rotates about an axis O via a thrust collar 22 that is disposed protruding from the rotating shaft 2 toward an outer side Dro in a radial direction Dr. The thrust bearing 6 comprises: a first bearing assembly 7 that is disposed on a first side in the axial direction Da with respect to the thrust collar 22; and a second bearing assembly 8 that is opposite in the axial direction Da with respect to the first bearing assembly 7 with respect to the thrust collar 22 as a reference and that is disposed on a second side in the axial direction Da with respect to the thrust collar 22. The first bearing assembly 7 has a first pad surface 711 that faces the thrust collar 22 in the axial direction Da, and includes a plurality of first pad assemblies 71 that are disposed apart from each other in a circumferential direction Dc with respect to the thrust collar 22 and have the same shape; and a first pad assembly 71 that is inserted from the outer side Dro in the radial direction Dr and that is disposed in a first predetermined position. the second bearing assembly 8 has a second pad surface 811 facing the thrust collar 22 in the axial direction Da, and a plurality of second pad assemblies 81 having the same shape and spaced apart in the circumferential direction Dc from the thrust collar 22; and second carrying cases 85, 85A having second insertion grooves 851 capable of holding the second pad assemblies 81 inserted from the outside Dro in the radial direction Dr at a second predetermined position, and defining the positions of the plurality of second pad assemblies 81, the first insertion grooves 751, 751A being formed in a shape that prevents the second pad assembly 81 from being inserted up to the first predetermined position, and the second insertion groove 851 being formed in a shape that prevents the first pad assembly 71 from being inserted up to the second predetermined position.

[0087] As a result, the first pad assembly 71 is inserted into the first insertion hole from the outer side Dro in the radial direction Dr, whereby the first pad assembly 71 is assembled to the first carrying case 75, 75A to form the first bearing assembly 7. Similarly, the second pad assembly 81 is inserted into the second insertion hole from the outer side Dro in the radial direction Dr, whereby the second pad assembly 81 is assembled to the second carrying case 85, 85A to form the second bearing assembly 8. This ensures ease of installation when attaching the first pad assembly 71 and the second pad assembly 81. Furthermore, the first insertion grooves 751, 751A can hold the first pad assembly 71 at a first predetermined position, but prevent the second pad assembly 81 from being inserted up to the first predetermined position. The second insertion groove 851 can hold the second pad assembly 81 at a second predetermined position, but prevent the first pad assembly 71 from being inserted up to the second predetermined position. Therefore, the second pad assembly 81 cannot be attached to the first carrying case 75, 75A while the attachability of the first pad assembly 71 to the first carrying case 75, 75A is ensured. Similarly, the first pad assembly 71 cannot be attached to the second carrying case 85, 85A while the attachability of the second pad assembly 81 to the second carrying case 85, 85A is ensured. As a result, it is possible to prevent the second pad assembly 81 from being erroneously attached to the first carrying case 75, 75A, or the first pad assembly 71 from being erroneously attached to the second carrying case 85, 85A. In this way, it is possible to prevent incorrect combinations of parts from being attached to the thrust bearing 6, thereby reducing incorrect assembly.

[0088] (2) A thrust bearing 6 according to a second aspect is the thrust bearing 6 of (1), wherein the first insertion grooves 751, 751A are configured such that, when the first pad assembly 71 is inserted, the first pad assembly 71 does not protrude from the outer peripheral surface of the first carrying case 75, 75A to the outside Dro in the radial direction Dr, and when the second pad assembly 81 is inserted, the second pad assembly 81 protrudes from the outer peripheral surface of the first carrying case 75, 75A to the outside Dro in the radial direction Dr. The second insertion groove 851 is formed in a shape such that, when the second pad assembly 81 is inserted, the second pad assembly 81 does not protrude from the outer peripheral surface of the second carrying case 85, 85A to the outside Dro in the radial direction Dr, and when the first pad assembly 71 is inserted, the first pad assembly 71 protrudes from the outer peripheral surface of the second carrying case 85, 85A to the outside Dro in the radial direction Dr.

[0089] As a result, components protrude from the outer peripheral surface of the first carrying case 75, 75A or the second carrying case 85, 85A only if the wrong first pad assembly 71 or second pad assembly 81 is attached. Therefore, if the second pad assembly 81 is attached to the first carrying case 75, 75A by mistake, or if the first pad assembly 71 is attached to the second carrying case 85, 85A by mistake, assembly cannot be completed. This makes it possible to immediately identify any assembly errors.

[0090] (3) A thrust bearing 6 according to a third aspect is the thrust bearing 6 according to (1) or (2), wherein the first carrying case 75, 75A is disposed between the adjacent first pad assemblies 71 and has a plurality of first oil supply nozzles 752, 752A that spray lubricating oil toward the thrust collar 22, and a first case body 753, 753A to which the plurality of first oil supply nozzles 752, 752A are fixed, and the second carrying case 85, 85A is disposed between the adjacent second pad assemblies 81 and has a plurality of second oil supply nozzles 852, 752A that spray lubricating oil toward the thrust collar 22. 52, and a second case body 853 to which a plurality of the second fuel fill nozzles 852 are fixed, the first insertion grooves 751, 751A are formed between two of the first fuel fill nozzles 752, 752A adjacent to each other in the circumferential direction Dc, and when the second pad assembly 81 is inserted, the second pad assembly 81 comes into contact with the first case body 753, 753A, and the second insertion groove 851 is formed between two of the second fuel fill nozzles 852 adjacent to each other in the circumferential direction Dc, and when the first pad assembly 71 is inserted, the first pad assembly 71 comes into contact with the second case body 853.

[0091] This makes it possible to prevent the second pad assembly 81 from being erroneously attached to the first carrying case 75, 75A, or the first pad assembly 71 from being erroneously attached to the second carrying case 85, 85A, simply by changing the shapes of the first case body 753, 753A and the second case body 853. Furthermore, the shapes of the first insertion groove 751, 751A and the second insertion groove 851 can be changed without being affected by the shapes of the first fuel filler nozzle 752, 752A and the second fuel filler nozzle 852.

[0092] (4) A thrust bearing 6 according to a fourth aspect is the thrust bearing 6 according to any one of (1) to (3), wherein the first carrying case 75, 75A is disposed between the adjacent first pad assemblies 71 and has a plurality of first oil supply nozzles 752, 752A that spray lubricating oil toward the thrust collar 22, and a first case body 753, 753A to which the plurality of first oil supply nozzles 752, 752A are fixed, and the second carrying case 85, 85A is disposed between the adjacent second pad assemblies 81 and has a plurality of second oil supply nozzles 852 that spray lubricating oil toward the thrust collar 22, and a first case body 753, 753A to which the plurality of second oil supply nozzles 752, 752A are fixed. and a second case body 853 to which an oil nozzle 852 is fixed, the first insertion grooves 751, 751A being formed in the first case body 753, 753A between two adjacent first fuel filler nozzles 752, 752A in the circumferential direction Dc, and when the second pad assembly 81 is inserted, the second pad assembly 81 comes into contact with the first fuel filler nozzle 752, 752A, and the second insertion groove 851 being formed in the second case body 853 between two adjacent second fuel filler nozzles 852 in the circumferential direction Dc, and when the first pad assembly 71 is inserted, the first pad assembly 71 comes into contact with the second fuel filler nozzle 852.

[0093] This makes it possible to prevent the second pad assembly 81 from being mistakenly attached to the first carrying case 75, 75A, or the first pad assembly 71 from being mistakenly attached to the second carrying case 85, 85A, simply by changing the shapes of the first fuel filler nozzle 752, 752A and the second fuel filler nozzle 852. Furthermore, because the shapes of the first fuel filler nozzle 752, 752A and the second fuel filler nozzle 852 are different, which makes them easy to recognize from the outside, the first carrying case 75, 75A and the second carrying case 85, 85A can be easily recognized.

[0094] (5) A thrust bearing 6 according to a fifth aspect is the thrust bearing 6 according to any one of (1) to (4), and includes a bearing cover 9 capable of accommodating the first bearing assembly 7 and the second bearing assembly 8 therein, first keys 11, 11B, 11C that determine the position of the first bearing assembly 7 in the circumferential direction Dc relative to the bearing cover 9, and a second key 15 that determines the position of the first bearing assembly 7 in the circumferential direction Dc relative to the bearing cover 9, wherein the first keys 11, 11B, 11C are received in first key grooves 110 formed in the first carrying cases 75, 75A and the bearing cover 9, and the second key 15 is inserted into the second carrying case 85, 85A and the second key groove 150 formed in the bearing cover 9, and the first keys 11, 11B, 11C and the second keys 15 are formed in one of the following shapes: a shape in which the first keys 11, 11B, 11C cannot be accommodated in the second key groove 150 and the second key 15 cannot be accommodated in the first key groove 110; a shape in which the first keys 11, 11B, 11C cannot be accommodated in the second key groove 150 and the second key 15 can be accommodated in the first key groove 110; or a shape in which the first keys 11, 11B, 11C can be accommodated in the second key groove 150 and the second key 15 cannot be accommodated in the first key groove 110.

[0095] As a result, it is not possible to assemble the first bearing assembly 7 and the second bearing assembly 8 to the bearing cover 9. Therefore, if the mounting positions of the first bearing assembly 7 and the second bearing assembly 8 relative to the thrust collar 22 are reversed, assembly cannot be completed. This makes it possible to immediately detect an error in the mounting positions of the first bearing assembly 7 and the second bearing assembly 8.

[0096] (6) The thrust bearing 6 according to the sixth aspect is any one of the thrust bearings 6 of (1) to (5), and the first bearing assembly 7 and the second bearing assembly 8 have the same axial dimension Da.

[0097] This means that even if the external shapes of the first bearing assembly 7 and the second bearing assembly 8 are similar, errors in the installation positions of the first bearing assembly 7 and the second bearing assembly 8 can be immediately detected by simply changing the shapes of the first keys 11, 11B, and 11C.

[0098] (7) A rotary machine according to a seventh aspect includes the thrust bearing 6 according to any one of (1) to (5) and the rotary shaft 2 rotatably supported by the thrust bearing 6.

[0099] This makes it possible to prevent parts from being assembled incorrectly in the first bearing assembly 7 and the second bearing assembly 8. Therefore, it is possible to prevent work errors when assembling the steam turbine 1 and improve workability. [Explanation of symbols]

[0100] 1. Steam turbine O…Axis line S...Steam 2...Rotation axis 21...Rotating shaft body 22...Thrust collar 23...Rotating blade row 24... Moving blade 3...Casing 31…Main channel 4...Stator blade row 41...Stationary blade 5...Bearing part 51...Journal bearing 6, 6A, 6B...Thrust bearing 7...First bearing assembly 71...First pad assembly 711...First pad surface 712...Back of the first pad 713...First pivot 75,75A...First carrying case 751, 751A...First insertion groove 752, 752A...First fuel nozzle 753, 753A...First case body 8...Second bearing assembly 81...Second pad assembly 811...Second pad surface 812...Back of the second pad 813...Second pivot 85, 85A...Second carrying case 851, 851A...Second insertion groove 852, 852A... Second fuel nozzle 853, 853A...Second case body 9...Bearing cover 11, 11B, 11C...First key 110...First keyway 111...Inner first keyway 112...Outer first keyway 15...Second key 150...Second keyway 151...Inner second keyway 152...Outer second keyway Da...Axial direction Dau…upstream Dad…downstream Dr…Radial direction Dri…inside Dro...outside Dc…Circumferential direction R...Rotation direction Rf...Front Rb…Backward

Claims

1. A thrust bearing that supports an axial load of a rotating shaft that rotates about an axis via a thrust collar that is disposed so as to protrude radially outward from the rotating shaft, a first bearing assembly disposed on the first axial side of the thrust collar; a second bearing assembly disposed axially opposite to the first bearing assembly relative to the thrust collar and on a second side of the thrust collar in the axial direction, the first bearing assembly a plurality of first pad assemblies each having a first pad surface facing the thrust collar in the axial direction, the first pad assemblies being spaced apart in a circumferential direction relative to the thrust collar and having the same shape; a first carrying case having a first insertion groove formed therein that can hold the first pad assembly inserted from the radially outer side at a first predetermined position, and that defines the positions of the plurality of first pad assemblies; the second bearing assembly a plurality of second pad assemblies having the same shape and spaced apart from each other in the circumferential direction relative to the thrust collar, the second pad assemblies having second pad surfaces facing each other in the axial direction relative to the thrust collar; a second carrying case having a second insertion groove formed therein that can hold the second pad assembly inserted from the radially outer side at a second predetermined position, and that defines the positions of the plurality of second pad assemblies; the first insertion groove is formed in a shape that prevents the second pad assembly from being inserted up to the first predetermined position; The second insertion groove is formed in a shape that prevents the first pad assembly from being inserted up to the second specified position in a thrust bearing.

2. The first insertion groove is When the first pad assembly is inserted, the first pad assembly does not protrude outward in the radial direction from an outer peripheral surface of the first carrying case, When the second pad assembly is inserted, the second pad assembly is formed in a shape that protrudes radially outward from an outer peripheral surface of the first carrying case, The second insertion groove is When the second pad assembly is inserted, the second pad assembly does not protrude outward in the radial direction from the outer circumferential surface of the second carrying case, 2. A thrust bearing as described in claim 1, wherein the first pad assembly is formed in a shape such that when the first pad assembly is inserted, the first pad assembly protrudes radially outward from the outer peripheral surface of the second carrying case.

3. the first carrying case is disposed between adjacent first pad assemblies and includes a plurality of first oil supply nozzles that spray lubricating oil toward the thrust collar, and a first case body to which the plurality of first oil supply nozzles are fixed; the second carrying case is disposed between adjacent second pad assemblies and includes a plurality of second oil supply nozzles that spray lubricating oil toward the thrust collar, and a second case body to which the plurality of second oil supply nozzles are fixed; the first insertion groove is formed between two of the first fuel filler nozzles adjacent to each other in the circumferential direction, and the second pad assembly and the first case body come into contact with each other when the second pad assembly is inserted into the first insertion groove; 3. A thrust bearing according to claim 1, wherein the second insertion groove is formed between two second fuel filler nozzles adjacent to each other in the circumferential direction, and the first pad assembly and the second case body come into contact with each other when the first pad assembly is inserted.

4. the first carrying case is disposed between adjacent first pad assemblies and includes a plurality of first oil supply nozzles that spray lubricating oil toward the thrust collar, and a first case body to which the plurality of first oil supply nozzles are fixed; the second carrying case is disposed between adjacent second pad assemblies and includes a plurality of second oil supply nozzles that spray lubricating oil toward the thrust collar, and a second case body to which the plurality of second oil supply nozzles are fixed; the first insertion groove is formed in the first case body between two of the first fuel filler nozzles adjacent to each other in the circumferential direction, and the second pad assembly and the first fuel filler nozzle come into contact with each other when the second pad assembly is inserted; 3. A thrust bearing according to claim 1, wherein the second insertion groove is formed in the second case body between two second fuel filler nozzles adjacent to each other in the circumferential direction, and the first pad assembly and the second fuel filler nozzle come into contact with each other when the first pad assembly is inserted.

5. a bearing cover capable of accommodating the first bearing assembly and the second bearing assembly therein; a first key that defines the circumferential position of the first bearing assembly relative to the bearing cover; a second key that defines the circumferential position of the first bearing assembly relative to the bearing cover; the first key is received in a first key groove formed in the first carrying case and the bearing cover; the second key is received in a second key groove formed in the second carrying case and the bearing cover; 3. A thrust bearing according to claim 1, wherein the first key and the second key are formed in one of the following shapes: a shape in which the first key cannot be accommodated in the second key groove and a shape in which the second key cannot be accommodated in the first key groove; a shape in which the first key cannot be accommodated in the second key groove and a shape in which the second key can be accommodated in the first key groove; or a shape in which the first key can be accommodated in the second key groove and a shape in which the second key cannot be accommodated in the first key groove.

6. 3. A thrust bearing according to claim 1, wherein the first bearing assembly and the second bearing assembly have the same axial size.

7. A thrust bearing according to claim 1 or 2; the rotating shaft rotatably supported by the thrust bearing.

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